3 #include <ccan/typesafe_cb/typesafe_cb.h>
6 /* You can use this directly to build tables, but the macros will ensure
7 * consistency and type safety. */
9 OPT_NOARG = 1, /* -f/--foo */
10 OPT_HASARG = 2, /* -f arg/--foo=arg/--foo arg */
11 OPT_SUBTABLE = 4, /* Actually, longopt points to a subtable... */
12 OPT_END = 8, /* End of the table. */
15 /* Maximum length of arg to show in opt_usage */
16 #define OPT_SHOW_LEN 80
19 const char *names; /* slash-separated names, --longopt or -s */
21 char *(*cb)(void *arg); /* OPT_NOARG */
22 char *(*cb_arg)(const char *optarg, void *arg); /* OPT_HASARG */
23 void (*show)(char buf[OPT_SHOW_LEN], const void *arg);
29 * OPT_WITHOUT_ARG() - macro for initializing an opt_table entry (without arg)
30 * @names: the names of the option eg. "--foo", "-f" or "--foo/-f/--foobar".
31 * @cb: the callback when the option is found.
32 * @arg: the argument to hand to @cb.
33 * @desc: the description for opt_usage(), or opt_hidden.
35 * This is a typesafe wrapper for intializing a struct opt_table. The callback
36 * of type "char *cb(type *)", "char *cb(const type *)" or "char *cb(void *)",
37 * where "type" is the type of the @arg argument.
39 * If the @cb returns non-NULL, opt_parse() will stop parsing, use the
40 * returned string to form an error message for errlog(), free() the
41 * string and return false.
43 * Any number of equivalent short or long options can be listed in @names,
44 * separated by '/'. Short options are a single hyphen followed by a single
45 * character, long options are two hypens followed by one or more characters.
50 #define OPT_WITHOUT_ARG(names, cb, arg, desc) \
51 { (names), OPT_CB_NOARG((cb), (arg)), (desc) }
54 * OPT_WITH_ARG() - macro for initializing long and short option (with arg)
55 * @names: the option names eg. "--foo=<arg>", "-f" or "-f/--foo <arg>".
56 * @cb: the callback when the option is found (along with <arg>).
57 * @show: the callback to print the value in get_usage (or NULL)
58 * @arg: the argument to hand to @cb and @show
59 * @desc: the description for opt_usage(), or opt_hidden.
61 * This is a typesafe wrapper for intializing a struct opt_table. The callback
62 * is of type "char *cb(const char *, type *)",
63 * "char *cb(const char *, const type *)" or "char *cb(const char *, void *)",
64 * where "type" is the type of the @arg argument. The first argument to the
65 * @cb is the argument found on the commandline.
67 * Similarly, if @show is not NULL, it should be of type "void *show(char *,
68 * const type *)". It should write up to OPT_SHOW_LEN bytes into the first
69 * argument; unless it uses the entire OPT_SHOW_LEN bytes it should
70 * nul-terminate that buffer.
72 * Any number of equivalent short or long options can be listed in @names,
73 * separated by '/'. Short options are a single hyphen followed by a single
74 * character, long options are two hypens followed by one or more characters.
75 * A space or equals in @names is ignored for parsing, and only used
76 * for printing the usage.
78 * If the @cb returns non-NULL, opt_parse() will stop parsing, use the
79 * returned string to form an error message for errlog(), free() the
80 * string and return false.
85 #define OPT_WITH_ARG(name, cb, show, arg, desc) \
86 { (name), OPT_CB_ARG((cb), (show), (arg)), (desc) }
89 * OPT_SUBTABLE() - macro for including another table inside a table.
90 * @table: the table to include in this table.
91 * @desc: description of this subtable (for opt_usage()) or NULL.
93 #define OPT_SUBTABLE(table, desc) \
94 { (const char *)(table), OPT_SUBTABLE, \
95 sizeof(_check_is_entry(table)) ? NULL : NULL, NULL, NULL, NULL, (desc) }
98 * OPT_ENDTABLE - macro to create final entry in table.
100 * This must be the final element in the opt_table array.
102 #define OPT_ENDTABLE { NULL, OPT_END }
105 * opt_register_table - register a table of options
106 * @table: the table of options
107 * @desc: description of this subtable (for opt_usage()) or NULL.
109 * The table must be terminated by OPT_ENDTABLE.
112 * static int verbose = 0;
113 * static struct opt_table opts[] = {
114 * OPT_WITHOUT_ARG("--verbose", opt_inc_intval, &verbose,
115 * "Verbose mode (can be specified more than once)"),
116 * OPT_WITHOUT_ARG("-v", opt_inc_intval, &verbose,
117 * "Verbose mode (can be specified more than once)"),
118 * OPT_WITHOUT_ARG("--usage", opt_usage_and_exit,
119 * "args...\nA silly test program.",
120 * "Print this message."),
125 * opt_register_table(opts, NULL);
127 void opt_register_table(const struct opt_table table[], const char *desc);
130 * opt_register_noarg - register an option with no arguments
131 * @names: the names of the option eg. "--foo", "-f" or "--foo/-f/--foobar".
132 * @cb: the callback when the option is found.
133 * @arg: the argument to hand to @cb.
134 * @desc: the verbose desction of the option (for opt_usage()), or NULL.
136 * This is used for registering a single commandline option which takes
139 * The callback is of type "char *cb(type *)", "char *cb(const type *)"
140 * or "char *cb(void *)", where "type" is the type of the @arg
143 * If the @cb returns non-NULL, opt_parse() will stop parsing, use the
144 * returned string to form an error message for errlog(), free() the
145 * string and return false.
147 #define opt_register_noarg(names, cb, arg, desc) \
148 _opt_register((names), OPT_CB_NOARG((cb), (arg)), (desc))
151 * opt_register_arg - register an option with an arguments
152 * @names: the names of the option eg. "--foo", "-f" or "--foo/-f/--foobar".
153 * @cb: the callback when the option is found.
154 * @show: the callback to print the value in get_usage (or NULL)
155 * @arg: the argument to hand to @cb.
156 * @desc: the verbose desction of the option (for opt_usage()), or NULL.
158 * This is used for registering a single commandline option which takes
161 * The callback is of type "char *cb(const char *, type *)",
162 * "char *cb(const char *, const type *)" or "char *cb(const char *, void *)",
163 * where "type" is the type of the @arg argument. The first argument to the
164 * @cb is the argument found on the commandline.
166 * At least one of @longopt and @shortopt must be non-zero. If the
167 * @cb returns false, opt_parse() will stop parsing and return false.
170 * static char *explode(const char *optarg, void *unused)
172 * errx(1, "BOOM! %s", optarg);
175 * opt_register_arg("--explode/--boom", explode, NULL, NULL, opt_hidden);
177 #define opt_register_arg(names, cb, show, arg, desc) \
178 _opt_register((names), OPT_CB_ARG((cb), (show), (arg)), (desc))
181 * opt_parse - parse arguments.
182 * @argc: pointer to argc
184 * @errlog: the function to print errors
186 * This iterates through the command line and calls callbacks registered with
187 * opt_register_table()/opt_register_arg()/opt_register_noarg(). If there
188 * are unknown options, missing arguments or a callback returns false, then
189 * an error message is printed and false is returned.
191 * On success, argc and argv are adjusted so only the non-option elements
192 * remain, and true is returned.
195 * if (!opt_parse(&argc, argv, opt_log_stderr)) {
196 * printf("You screwed up, aborting!\n");
201 * opt_log_stderr, opt_log_stderr_exit
203 bool opt_parse(int *argc, char *argv[], void (*errlog)(const char *fmt, ...));
206 * opt_log_stderr - print message to stderr.
207 * @fmt: printf-style format.
209 * This is a helper for opt_parse, to print errors to stderr.
212 * opt_log_stderr_exit
214 void opt_log_stderr(const char *fmt, ...);
217 * opt_log_stderr_exit - print message to stderr, then exit(1)
218 * @fmt: printf-style format.
220 * Just like opt_log_stderr, only then does exit(1). This means that
221 * when handed to opt_parse, opt_parse will never return false.
224 * // This never returns false; just exits if there's an erorr.
225 * opt_parse(&argc, argv, opt_log_stderr_exit);
227 void opt_log_stderr_exit(const char *fmt, ...);
230 * opt_invalid_argument - helper to allocate an "Invalid argument '%s'" string
231 * @arg: the argument which was invalid.
233 * This is a helper for callbacks to return a simple error string.
235 char *opt_invalid_argument(const char *arg);
238 * opt_usage - create usage message
239 * @argv0: the program name
240 * @extra: extra details to print after the initial command, or NULL.
242 * Creates a usage message, with the program name, arguments, some extra details
243 * and a table of all the options with their descriptions. If an option has
244 * description opt_hidden, it is not shown here.
246 * If "extra" is NULL, then the extra information is taken from any
247 * registered option which calls opt_usage_and_exit(). This avoids duplicating
248 * that string in the common case.
250 * The result should be passed to free().
252 char *opt_usage(const char *argv0, const char *extra);
255 * opt_hidden - string for undocumented options.
257 * This can be used as the desc parameter if you want an option not to be
258 * shown by opt_usage().
260 extern const char opt_hidden[];
262 /* Standard helpers. You can write your own: */
263 /* Sets the @b to true. */
264 char *opt_set_bool(bool *b);
265 /* Sets @b based on arg: (yes/no/true/false). */
266 char *opt_set_bool_arg(const char *arg, bool *b);
267 void opt_show_bool(char buf[OPT_SHOW_LEN], const bool *b);
269 char *opt_set_invbool(bool *b);
270 void opt_show_invbool(char buf[OPT_SHOW_LEN], const bool *b);
271 /* Sets @b based on !arg: (yes/no/true/false). */
272 char *opt_set_invbool_arg(const char *arg, bool *b);
275 char *opt_set_charp(const char *arg, char **p);
276 void opt_show_charp(char buf[OPT_SHOW_LEN], char *const *p);
278 /* Set an integer value, various forms. Sets to 1 on arg == NULL. */
279 char *opt_set_intval(const char *arg, int *i);
280 void opt_show_intval(char buf[OPT_SHOW_LEN], const int *i);
281 char *opt_set_uintval(const char *arg, unsigned int *ui);
282 void opt_show_uintval(char buf[OPT_SHOW_LEN], const unsigned int *ui);
283 char *opt_set_longval(const char *arg, long *l);
284 void opt_show_longval(char buf[OPT_SHOW_LEN], const long *l);
285 char *opt_set_ulongval(const char *arg, unsigned long *ul);
286 void opt_show_ulongval(char buf[OPT_SHOW_LEN], const unsigned long *ul);
289 char *opt_inc_intval(int *i);
291 /* Display version string to stdout, exit(0). */
292 char *opt_version_and_exit(const char *version);
294 /* Display usage string to stdout, exit(0). */
295 char *opt_usage_and_exit(const char *extra);
297 /* Below here are private declarations. */
298 /* Resolves to the four parameters for non-arg callbacks. */
299 #define OPT_CB_NOARG(cb, arg) \
301 cast_if_any(char *(*)(void *), (cb), &*(cb), \
302 char *(*)(typeof(*(arg))*), \
303 char *(*)(const typeof(*(arg))*), \
304 char *(*)(const void *)), \
307 /* Resolves to the four parameters for arg callbacks. */
308 #define OPT_CB_ARG(cb, show, arg) \
310 cast_if_any(char *(*)(const char *,void *), (cb), &*(cb), \
311 char *(*)(const char *, typeof(*(arg))*), \
312 char *(*)(const char *, const typeof(*(arg))*), \
313 char *(*)(const char *, const void *)), \
314 cast_if_type(void (*)(char buf[], const void *), (show), &*(show), \
315 void (*)(char buf[], const typeof(*(arg))*)), \
318 /* Non-typesafe register function. */
319 void _opt_register(const char *names, enum opt_type type,
320 char *(*cb)(void *arg),
321 char *(*cb_arg)(const char *optarg, void *arg),
322 void (*show)(char buf[OPT_SHOW_LEN], const void *arg),
323 void *arg, const char *desc);
325 /* We use this to get typechecking for OPT_SUBTABLE */
326 static inline int _check_is_entry(struct opt_table *e) { return 0; }
328 #endif /* CCAN_OPT_H */